KML 图层将无法正确切换，谷歌地图

KML Layer Will Not Toggle Properly, Google Maps

本文关键字：谷歌地图图层 KML 更新时间：2023-09-26

我正在使用Google Maps API和KML创建交互式校园地图。我有一张带有地面叠加层和 KML 标记层的地图。我正在尝试弄清楚如何让 KML 图层切换。我目前已将其设置为通过复选框切换，但它仅在您第一次单击复选框时关闭。任何后续单击都不执行任何操作。KML 图层将消失。我有一种感觉，这可能是一个简单的javascript修复，但我是javascript的新手，我无法弄清楚。有人知道我做错了什么吗？提前感谢您的帮助。

这是我的所有代码：

<script type="text/javascript">
  function initialize() {
  var map;
  var omaha = new google.maps.LatLng(41.265437, -95.947405);
  var MY_MAPTYPE_ID = 'blue';
  var stylez = [
    {
      featureType: "all",
      stylers: [
        { hue: "#004A96" },
      ]
    },
    {
      featureType: "all",
      elementType: "labels",
      stylers: [
        { hue: "#000000" },
      ]
    },
        {
      featureType: "road",
      elementType: "local",
      stylers: [
        { hue: "#24356B" },
        { saturation: 55 },
        { lightness: 20 }
      ]
    },
    {
      featureType: "poi.school",
      elementType: "geometry",
      stylers: [
        { hue: "#24356B" },
        { saturation: 55 },
        { lightness: 20 }
      ]
    }
  ];
  var imageBounds = new google.maps.LatLngBounds(
      new google.maps.LatLng(41.2599,-95.9601),
      new google.maps.LatLng(41.2718,-95.9367));
  var mapOptions = {
    zoom: 15,
    center: omaha,
    mapTypeControlOptions: {
        mapTypeIds: [google.maps.MapTypeId.ROADMAP, MY_MAPTYPE_ID]
    },
    mapTypeId: MY_MAPTYPE_ID
  };
  var map = new google.maps.Map(document.getElementById("map_canvas"), mapOptions);
  var styledMapOptions = {
    name: "Blue"
  };
  var jayzMapType = new google.maps.StyledMapType(stylez, styledMapOptions);
  map.mapTypes.set(MY_MAPTYPE_ID, jayzMapType);
  var oldmap = new google.maps.GroundOverlay(
      "http://www.mcography.com/beta/CampusMap.png",
      imageBounds);
  oldmap.setMap(map);
  var kmlLayer01URL = 'http://www.mcography.com/beta/CUADA.kml';
  var kmlOptions = {
            preserveViewport: 1
    };
    kmlLayer01 = new google.maps.KmlLayer(kmlLayer01URL, kmlOptions);
    kmlLayer01.setMap(map); 
    // initially show KML Layer 01
    document.getElementById('show_hide_KML_Layer_01').checked = true; 
}
function toggleKMLLayer01() {
    if (!document.getElementById('show_hide_KML_Layer_01').checked)
      kmlLayer01.setMap(null);
    else
      kmlLayer01.setMap(map); }
</script>
</head>
<body onload="initialize()">
    <p><input type="checkbox" id="show_hide_KML_Layer_01" onclick="toggleKMLLayer01();" />ADA Layer</p> 
    <div id="map_canvas"></div>
</body>

如果没有代码的顶部，我不能完全确定，但我的预感是你需要将map变量设为全局变量，否则toggle不会setMap map。我写了以下内容，有效：

  var map;
  function initialize() {
    var mapOptions = { center: new google.maps.LatLng(0.0, 0.0), zoom: 2,
      mapTypeId: google.maps.MapTypeId.ROADMAP };
    map = new google.maps.Map(document.getElementById("map_canvas"), mapOptions);
    var kmlLayer01URL = 'http://www.mcography.com/beta/CUADA.kml';
    var kmlOptions = {
      preserveViewport: 1
    };
    kmlLayer01 = new google.maps.KmlLayer(kmlLayer01URL, kmlOptions);
    kmlLayer01.setMap(map); 
    // initially show KML Layer 01
    document.getElementById('show_hide_KML_Layer_01').checked = true; 
  }
  function toggleKMLLayer01() {
    if (!document.getElementById('show_hide_KML_Layer_01').checked)
      kmlLayer01.setMap(null);
    else
      kmlLayer01.setMap(map); 
  }